I'm having a bit of trouble figuring out what the problem is on our 2005 GD Sport, its the one with the climate control dash.

There are two problems which may or may not be related as they started to occur around the same time.

1. The illumination of the speedo dashboard etc flickers.2. The symbol illumination on the A/C, MODE, Demister and Window/Mirror Heater buttons have stopped working although the little light on the button (Green/Orange) still work.

I was planning to take the radio out to replace the bulbs but thought that it is unlikely that all 4 bulbs have blown at the same time and for all 4 to be next to each other seems very unlikely. Furthermore, I couldn't find the type of bulb it needs anyhow.

There are only a couple of bulbs behind the heater controls with perspex light guides carrying the illumination to each button. It's quite a unique little bulb, I've got the details somewhere. When one bulb goes the neighbours are often next as anyone with halogen downlights at home can attest. The LCD has a standard backlight.

Have you given the dash light brightness control on the mpg/trip button a bit of a twist to exercise it? The next item upstream is the taillight relay so you should be able to rule that out easily.-- TG

There are only a couple of bulbs behind the heater controls with perspex light guides carrying the illumination to each button. It's quite a unique little bulb, I've got the details somewhere. When one bulb goes the neighbours are often next as anyone with halogen downlights at home can attest. The LCD has a standard backlight.

Have you given the dash light brightness control on the mpg/trip button a bit of a twist to exercise it? The next item upstream is the taillight relay so you should be able to rule that out easily.-- TG

Thanks for this. I assumed that each button had it's own bulb. But if there's one bulbs for 4 buttons (say) that would make sense.

Would you by any chance know the bulb type to save me having to dismantle the dash just to find out? I had a look in Halfords for replacement bulbs but they don't seem to do any of the sort. So I will have to look online but can't seem to find the bulb type.

As with the dash brightness, no I have tried changing the brightness control, will give that a go.

Sorry I don't understand what you mean by the tailgate relay and how to eliminate that - I don't understand how that is related to the dash illumination?

Mine blew and I had to replace the bulbs. I could not find the details of them. Once I got the radio out I found some marking on the bulb and rang the dealer. They wanted £5.00ish per bulb before vat.

I found leds online for much cheaper. The only problem with the leds is that I had to sand down all the edges to get them to fit in the hole. Also leds only work in one direction so I had to take some out and change them around to get them to work.

It has been fine ever since.

I am on my phone so I can't give you any details of the leds but I found them via google

Sorry I don't understand what you mean by the tailgate relay and how to eliminate that - I don't understand how that is related to the dash illumination?

The wiring for the dash lighting comes from the same source as the rear tail lights via a relay so if we know that's OK then any issue must be between that and the bulb. The dashboard has a power regulator and brightness control before distribution to each bulb.

I'll send a picture of the bulbs later on, you have to dismantle the panel to get them out even though it appears they should come out with a quarter twist.-- TG

Mine blew and I had to replace the bulbs. I could not find the details of them. Once I got the radio out I found some marking on the bulb and rang the dealer. They wanted £5.00ish per bulb before vat.

I found leds online for much cheaper. The only problem with the leds is that I had to sand down all the edges to get them to fit in the hole. Also leds only work in one direction so I had to take some out and change them around to get them to work.

It has been fine ever since.

I am on my phone so I can't give you any details of the leds but I found them via google

Would LEDs be too bright compared to the originals? And would I need to solder some resistors to get them to work? I think I might have some old white 5mm Nichia LEDs somewhere - are these the type you used?

Sorry I don't understand what you mean by the tailgate relay and how to eliminate that - I don't understand how that is related to the dash illumination?

The wiring for the dash lighting comes from the same source as the rear tail lights via a relay so if we know that's OK then any issue must be between that and the bulb. The dashboard has a power regulator and brightness control before distribution to each bulb.

I'll send a picture of the bulbs later on, you have to dismantle the panel to get them out even though it appears they should come out with a quarter twist.-- TG

Oh right, that makes sense. The tail lights are fine, so there could be a loose connection somewhere between the relay and the bulb. More investigation needed then...

I had the same problem on my GD sport with illumination on four of the switches. The same ones as yours. There are four lamps that illuminate the climate control area. Just one of these lamps light up the four switches. Part no 79674-s3n-941@ £3.51 + vat. These lamps come with the lamp holder. I replaced all four lamps. To replace lamps I removed the radio panel for access. Below the climate control, you can remove the panel. It is held in place by one Phillips screw. Switch on side lights and with the aid of a mirror you can see which lamp is out.